| | | ConnectX-5 | | ConnectX-5 |
+-----------------------+-----------------+-----------------+
+Notes for metadata
+------------------
+
+MARK and META items are interrelated with datapath - they might move from/to
+the applications in mbuf fields. Hence, zero value for these items has the
+special meaning - it means "no metadata are provided", not zero values are
+treated by applications and PMD as valid ones.
+
+Moreover in the flow engine domain the value zero is acceptable to match and
+set, and we should allow to specify zero values as rte_flow parameters for the
+META and MARK items and actions. In the same time zero mask has no meaning and
+should be rejected on validation stage.
+
Notes for testpmd
-----------------